**Introduction/Hypothesis:**
Erdheim-Chester Disease (ECD) is a rare disease of histiocytic neoplasm characterized by clonal expansion of foamy macrophages and inflammatory cells with progression to fibrotic changes in infiltrated tissues. This disease affects a wide range of organ systems, including skeletal, respiratory, renal, central nervous, and cardiovascular systems.
Cardiac Magnetic Resonance Imaging (CMR) or gated computed tomography (CT) are necessary for full cardiac assessment of patients with ECD. Timely recognition of cardiac complications is vital as prompt diagnosis and treatment with targeted inhibitors can lead to stabilization or resolution of cardiac manifestations.

**Methods**
We present CMR findings of three patients with pathology-confirmed ECD.

**Results**
The primary cardiac manifestations included infiltrative soft tissue mediastinal mass, atrioventricular sulcus infiltration, right atrial inflammatory pseudotumor, pericardial thickening and effusion, and aortic mural wall thickening.

**Conclusion**
CMR, with its superior tissue characterization and functional assessment, should be used to assess cardiac involvement in patients with suspected ECD to monitor disease progression and treatment response. CMR is non-invasive without ionizing radiation and can be employed with techniques like late gadolinium enhancement (LGE) and T1/T2 mapping to identify fibrotic, inflamed, and infiltrated tissues of patients with ECD.



At the Heart of the Matter: Cardiac Manifestations of Erdheim-Chester Disease

This course will explore basic and cutting-edge imaging techniques to improve patient care and hone individual skills in performance and interpretation of echocardiography, nuclear cardiology, cardiac computed tomography, and cardiovascular magnetic resonance imaging. Days will reinforce how cardiovascular imaging may improve comprehension in ischemic heart disease, structural heart disease, cardiomyopathies, and heart failure. Experts will utilize novel techniques to reinforce key topics including taped interventional cases and a strong emphasis on case presentations.